Revision as of 13:47, 13 August 2016

This article provides an introduction to the distribution of coastal sand dunes in Europe. It is based on a revised edition of the 'Sand Dune Inventory of Europe' (Doody ed. 1991) [1].

The 1991 inventory was prepared under the umbrella of the European Union for Dune Conservation [EUDC]. The original inventory was presented to the European Coastal Conservation Conference, held in the Netherlands in November 1991. It attempted to provide a description of the sand dune vegetation, sites and conservation issues throughout Europe including Scandinavia, the Atlantic coast and in the Mediterranean.

It is the main point of reference to the more detailed reports on individual countries prepared as part of a revised 'Sand Dune Inventory of Europe' presented at the International Sand Dune conference “Changing Perspectives in Coastal Dune Management”, held from the 31st March - 3rd April 2008, in Liverpool, UK (Doody ed. 2008)[2]. The conference was organised under the auspices of the Sand Dune and Shingle Network [1] and hosted by Liverpool Hope University.

Note the author has recently published a book on sand dune conservation and management which includes information on European dunes [3].

Introduction

Sand dunes border long stretches of the European coastline. They develop wherever there is a suitable supply of sediment moved onshore by the tide to form a beach. Where this dries, the wind blows the sediment inland to form accumulations a few centimetres to 40m or more thick. The type of sand dune landscape existing today is the product of a long history of a response to natural forces and human modification.

Habitat distribution

In the north and west, a wet climate coupled with their use for grazing stock (including rabbits) has helped create rich grasslands and heathlands. In many areas, overgrazing and misuse caused erosion resulting in blowing sand overwhelming villages and farms. Large areas were planted with exotic species, including a number of pine species in order to combat this. Open dynamic dune landscapes are today relatively restricted.

The figure shows the approximate location of the main areas of sand dunes in the regions described. Links are provided to individual country descriptions, which identify the major sand dune sites, their nature conservation significance and the factors affecting this. These include information on Protected Areas where available. Note that for the protected areas the inventory mostly relies on local information provided by the original contacts. An acknowledgement is made of new information.

In the Mediterranean, recreational pressures have caused the destruction of dunes with the construction of mass tourist facilities. In the process, they have obliterated many of the natural landscapes that attracted the visitor in the first place.

North east Atlantic: Celtic Seas, North Sea and Baltic Sea

Much of the coastline of the North East Atlantic coast formed from ancient rocks resistant to erosion. The absence of sedimentary material for the development of sand dunes mean that there are a relatively large number of small sites, many of which are associated with embayments. Exceptionally on west facing coasts, where the prevailing westerly winds reinforce the dominant winds, large hindshore systems have developed. In the Outer Hebrides in Scotland these include some of the best and largest examples of the extensive cultivated sandy plain or ‘machair’, also present in the west of Ireland. The way these influences effect the distribution and size of dunes is seen by reference to the situation in Great Britain.

In other areas of the northern parts of the Celtic and North Seas and in the Baltic Sea where dunes develop on coastlines which are rising relative to sea level, a sequence of prograding ridges may form as a sequence lying ‘parallel’ to the coast. They are sometimes interspersed with damp hollows in which rich dune slack vegetation develops. Examples include Magilligan [2] dunes in Northern Ireland, Morrich More [3]in northern Scotland and the Jaeres dunes (Site 7) of southern Norway,.

In the southern Baltic and southern North Sea, sand dunes can be extensive, for example, they make up 80% of the coastline of Poland. The extent and importance of the dunes of Denmark, the Wadden coast (including Germany) and the Netherlands cannot be over-emphasised. Coastal currents and the prevailing wind influence the direction and amount of transported material and hence the orientation of the dunes along the coast. Sand bars and spits, which lie parallel to the coast (Poland and Wadden Sea) are a predominant dune type. Elsewhere massive accumulations of sand are forced onshore under the action of the prevailing wind as, for example, northern Denmark and the Netherlands.

Most of the sand dunes described for north west Europe appear to have a sequence of vegetation types which potentially includes all the more important successional communities from strandline (driftwalls) to yellow and grey dune, dune pasture, heath and scrub. In areas where beach erosion is occurring some of the early stages of succession may be absent with the sand dune forming a cliff above the beach. In other mobile dunes may occur in the body of the dune creating early stages of succession similar to those of the upper beach. Many dune areas provide pasture for grazing animals and this has had a profound influence on the type of vegetation, which develops, particularly in the North West. Here grazing helps to create species-rich calcareous dune grassland and heathland, preventing the natural progression to scrub and woodland. Native woodlands are scarce, although there are examples of secondary mixed scrub, broad-leaved woodland and pine forest in areas formerly used for grazing domestic stock.

Eastern and Mid Atlantic coast: including the English Channel and Bay of Biscay

In the northern part of the area, dunes or dune remnants occur along many stretches of the coastline from western Ireland, south west Britain, northern France and Spain. The coast has a predominantly cliffed nature and the availability of suitable sedimentary material is restricted. Hence, as with the cliffed landscapes further north, dunes tend to be smaller and develop in sheltered embayments. Exceptions occur near estuaries, such as the Somme in France, and extensive dunes occur here.

Further south along the west facing coasts of France and Portugal, there is greater availability of material from fluvial sources. When combined with strong erosive action and long shore drift, large sediment transport systems develop. Both countries have strong, prevailing westerly winds and the dunes may stretch many kilometres inland. In France, for example, the area known as ‘Les Landes’ [4] has a special significance and is one of the most extensive dunes in Europe. 60% of the coastline of Portugal has sand dunes. They are mostly parabolic in form, especially in the west. However, the dune systems can be complex, containing different geomorphological types extending from a few metres to up to 6km inland.

The sequence of vegetation on the mid-Atlantic coast is similar to that occurring in the north west. This typically involves the progressive stabilisation of dune forms as sand blows inland and vegetation develops. In a number of areas, notably on the exposed Atlantic coast sand blows up and over cliffs to create a veneer of sand over the underlying rock. In the north of France, some of the botanically richer areas occur where dunes are composed of calcareous sand and lie against to chalk cliffs, as at le Nord de la Baie de Canche.

In south western Spain, the dune systems include barrier islands and spits found in western Andalucía on the southern Atlantic coast. Several river deltas by transporting sediment to the sea, helped to create one the most important dune systems in Europe, which lies within the Coto Doñana National Park [5]. The park consists of beaches, foredunes, high mobile dunes (up to 30m) and stabilised dunes, which enclose a major wetland.

Western Mediterranean

The further south the dunes, the more the southern elements of the flora begin to appear. Typically, in the Mediterranean open vegetation forms above the beach where Pancratium maritimum is a common species on the beach and in the dune. There is a less obvious successional development, though narrow zones of pioneer vegetation dominated by Elymus farctus and/or Ammophila arenaria are present. This grades into a grassland and scrub with the most frequently found vegetation dominated by shrubs to form garigue (an open dwarf shrub community about 60cm and rarely >1m high) and maquis (a dense shrub community >1m high) typical of grazed inland areas (Polunin & Walters 1985)[5]

On the western Mediterranean coast, dunes are narrower and often found in association with deltas. Along both the Spanish and French coasts tourist development has destroyed many of these systems, though the Camargue still retains much of its coastal character. In Italy, many of the dunes probably originated during the thermal optimum after the last glaciation (5,000 years ago). They have since been broken by rivers and their subsequent development has been a product of natural erosive forces and human development. Today dunes are present around the whole coastline but only in a few protected areas, like the National Park of Circeo, is it possible to see natural development.

Eastern Mediterranean and Black Sea

There are many places in the region where sand dunes cannot develop because the hills or mountains outcrop as rocky shorelines near to the sea. The coast of Croatia, the southern Albania border and many of the Greek islands are such. Throughout this area, sand dunes tend either to occupy a narrow fringe bordering flat areas of land or exceptionally form extensive dunes up to 10m height as in Western Peloponnesus, in Greece. In some areas, the dunes may reach a height of 20-30m.
In Turkey and along the northern shores of Albania almost all dune systems form in the immediate vicinity of rivers, sometimes as part of big delta systems. They often form a barrier to the sea and enclose a lakes or series of lakes (lagoons). Three very distinctive types of dunes are formed; deltas, on coastal plains and in bays. The maximum height is about 50m and they have a maximum width of up to for example 4.3km in south west Turkey. Many different dune forms are present, e.g. huge beach plains with embryo dunes, parabolic dunes, blowouts, dune slacks, lakes, secondary barchans and dune fields. In the Mediterranean systems, the calcium carbonate content is very high, while siliceous sands prevail along the Black Sea and Marmara coasts.

Sand dune country articles

Sand Dune Inventory of Europe (Doody ed. 1991 & 2008)
Sand dune articles for the following countries can also be accessed from here: